ASTM D4698-92(1996)

Standard Practice for Total Digestion of Sediment Samples for Chemical Analysis of Various Metals

SCOPE
1.1 This practice covers two procedures for the total digestion of sediments for subsequent determination of metals by such techniques as flame atomic absorption spectrophotometry, graphite-furnace atomic absorption spectrophotometry, atomic emission spectroscopy, etc.
1.2 This practice is applicable in the subsequent determination of volatile, semivolatile, and nonvolatile metals of sediments.
1.3 Actual metal quantitation can be accomplished by following the various test methods outlined under other appropriate ASTM standards for the metal(s) of interest. Before selecting either of the digestion techniques outlined in this practice, the user should consult the appropriate quantitation standard(s) for any special analytical considerations, and Practice D3976 for any special preparatory considerations.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For a specific hazard statement, see Note 7.
1.5 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

General Information

• Status: Historical
• Publication Date: 31-Dec-2000
• Technical Committee: D19 - Water
• Drafting Committee: D19.07 - Sediments, Geomorphology, and Open-Channel Flow

Relations

• Replaced By: ASTM D4698-92(2001) - Standard Practice for Total Digestion of Sediment Samples for Chemical Analysis of Various Metals
• Effective Date: 01-Jan-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or
withdrawn. Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4698 – 92 (Reapproved 1996)
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Practice for
Total Digestion of Sediment Samples for Chemical Analysis
1
of Various Metals
This standard is issued under the fixed designation D 4698; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope tice, refer to Terminology D 1129.
3.2 Definitions of Terms Specific to This Standard:
1.1 This practice covers two procedures for the total diges-
tion of sediments for subsequent determination of metals by 3.2.1 total digestion—the dissolution of a sediment matrix
such techniques as flame atomic absorption spectrophotometry, such that quantitation will produce a measurement which is
graphite-furnace atomic absorption spectrophotometry, atomic more than 95% of the constituent present in the sample.
emission spectroscopy, etc.
3.2.2 partial digestion—the dissolution of a sediment ma-
1.2 This practice is applicable in the subsequent determina-
trix such that quantitation will produce a measurement of less
tion of volatile, semivolatile, and nonvolatile metals of sedi-
than 95% of the constituent present in the sample. In such
ments.
cases, recovery is operationally defined by the digestion
1.3 Actual metal quantitation can be accomplished by fol-
procedure.
lowing the various test methods outlined under other appropri-
ate ASTM standards for the metal(s) of interest. Before
4. Summary of Practices
selecting either of the digestion techniques outlined in this
4.1 Many procedures are available for the total digestion of
practice, the user should consult the appropriate quantitation
sediments prior to metal analysis, but almost all the methods
standard(s) for any special analytical considerations, and Prac-
fall into one of two main classes: fusion and subsequent
tice D 3976 for any special preparatory considerations.
dissolution of the bead, and wet digestion which directly
1.4 This standard does not purport to address all of the
dissolves the sample with mineral acids. Each of the classes
safety concerns, if any, associated with its use. It is the
has advantages and disadvantages, as do the individual proce-
responsibility of the user of this standard to establish appro-
dures which fall under them. The two procedures outlined in
priate safety and health practices and determine the applica-
this practice were selected because they are the least restricted,
bility of regulatory limitations prior to use. For a specific
in terms of utility, for dealing with a wide variety of matrices.
hazard statement, see Note 7.
Before choosing a particular method, the user should consult
1.5 The values stated in inch-pound units are to be regarded
the pertinent literature to determine the utility and applicability
as the standard. The values given in parentheses are for
of either method, prior to final selection; or if a less rigorous
information only.
4,5,6,7
digestion could be employed. Even then, experience with
a particular sample type or digestion test method, or both, may
2. Referenced Documents
have to be the final arbiter in test method selection.
2.1 ASTM Standards:
2
4.2 Field collected samples should be treated according to
D 1129 Terminology Relating to Water
the procedures outlined in Practice D 3976.
D 1192 Specification for Equipment for Sampling Water
2
4.3 Dried samples are ground to finer than 100 mesh (150
and Steam in Closed Conduits
2
μm) using an appropriate grinding device or system.
D 1193 Specification for Reagent Water
D 3976 Practice for Preparation of Sediment Samples for
4.4 Procedure A—Fusion with lithium metaborate/
3
Chemical Analysis tetraborate.
4.5 Procedure B—Wet digestion using a combination of
3. Terminology
hydrofluoric, perchloric, and nitric acids.
3.1 Definitions—For definitions of terms used in this prac-
4
Johnson, W., and Maxwell, J., Rock and Mineral Analysis, 2nd Edition, John
1
This practice is under the jurisdiction of ASTM Committee D-19 on Water and Wiley & Sons, New York, 1981, p. 489.
5
is the direct responsibility of Subcommittee D 19.07 on Sediments, Geomorphology, Pinta, M., Modern Methods for Trace Element Analysis, Ann Arbor Science
and Open-Channel Flow. Publishers, Ann Arbor, 1982, pp. 133–264.
6
Current edition approved Oct. 15, 1992. Published December 1992. Originally Dolezal, J., Povondra, C., and Sulcek, Z., Decomposition Techniques in
published as D 4698 – 87. Last previous edition D 4698 – 87. Inorganic Analysis, Elsevier Publishing Co., New York, 1968
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